Conventionally, a vehicle door controlling device has been known that has a vehicle-side controller to receive a reservation signal from a mobile terminal, which transmits the reservation signal representing reservation of automatic door-opening of a vehicle door, when a user holding the mobile terminal approaches the door, and if detecting the user, executes door-unlocking and door-opening (for example, Patent Document 1).
[Patent Document 1] Japanese Laid-open Patent Publication No. 2009-024454
However, the vehicle door controlling device described in Patent Document 1 executes door-unlocking and door-opening, just by receiving the reservation signal transmitted from the mobile terminal, and detecting the user, and hence, the door may be opened against a circumstance around the vehicle and/or an intention of the user. For example, if an obstacle exists on a door-opening trajectory of the door, and the door-opening is executed just by receiving the reservation signal and detecting the user, the obstacle may come into contact with the door, and the door may be damaged. Also, it is likely to happen that the user forgets that he/she has made a reservation operation on the mobile terminal, the door may be opened in a circumstance where the user does not expect the door to open.